Friction-clutch.



A. KINGSBURY.

FBIGTION CLUTCH.

APPLICATION FILED AUG. 7, 1911.

4Patented Sept. 1, 1914.

A'nonNEY WITNESSES:

I LBERT KINGSBUBY, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELEGTRIC AND MANUFACTURING COMPANY,

' En sTATEs PATENT oFFioE.

A CORPORATION 0F PENNSYLVANIA.

FBIGTION-CLUTCH.

incassa.

Specification of Letters Patent.

application mea august 7,1911. serial No. euses.

To all whom it may concern.'

Be it known that I, ALBERT Knvosnonv, a citizen of the United States, and a resident of Pittsburgh in the county of Allegheny and State o Pennsylvania, have in vented a new and useful Improvement 1 n Friction-Clutches, of which the following is a specilication.

`My invention relates to friction clutches and particularly to such clutchesas are dependent upon centrifugal action for their operation. v y

The object of my invention is to provide a clutch which shall be simple and.dura ble in construction and capable of transmitting energy to a rotatable member with equal efficiency in either direction.

In Patent No. I$82,693, Westinghouse Electric &

rented to 'the anufacturing Company on 'an application tiled by me- March 6, 1905, I have shown and described a friction clutch comprising a l ioll ow cylindrcal member in which a resilient ring, d1-

' vided at one point in its circumference, is 1oport and the helical ranged helical spring,

cated, a s ring being arranged to draw the ends of the interrupted ring together and centrifugal action being depended upon to act-in op osition to the spring end the re siliency oi) the ring to force the ring into engagementwith the cylinder in w ich it is located..

According to my present invention, I provide an annular support on one member of the clutch and a concentric hollow cylindrical pulley on the opposing member of the clutch and interpose acircumferentially arwhich is located in a groove in the annular support and is provided with a tension spring, for causing it to wrap around the support. When the supspiing are rotated at a predetermined speed, the circumferential spring will expand and firmly grip the in-` ner cylindrical surface of the opposing niember`of the clutch.

verse sect-ion, of the parts shown in Figure l of the accompanying drawings is a longitudinal section of a clutch constructed in accordance with my invention.v

Fig. 2 is an end elevation, partially in trans- Fi s. 3 and 4 are detail views of the support an thcspring shown inthe other tigur.

Referring to the drawings, the clutch here shown comprises a pulley or other suitable member l which is secured to a rotatable Fig. 1.

shaft 2 and is provided with acircumferen tial Harigev 3, a sleeve or quill 4 rotatably mounted on the shaft 2, a support 5, securedto the sleeve or quill 4 within the flange 3, a

circumferentiall disposed `helical spring 6 and a tangential y disposed tension spring 7. An annular groove is provided in the outer cylindrical surface of the support 5 in which the helical spring 6 is disposed, the arrangement of parts. bein such that the turns of the spring engage t 1e bottom of the groove 8 and clear the inner cylindrical sur ace of the flange Bexcept when the sleeve 4 and the support 5 are rotating at a predeten mined speed. The spring f5 is preferably formed of steel wire of square or rectangular section, in order to provide a large bearing surface.

Clips secured to the respective ends of the spring 6 and extend inwardly through apertures l1 and l2, which are provided for that purpose in the periphery of the support 5, the relatively small tension spring 7 being interposed between the clips 9 and 10 and tending' to wrap the spring 6 about the su vport 5.

The support 5 is provided with 'stops 'I4 und 1.5 wit i which the respective ends of the spring 6 enga e durinithe operation. of the c utchv accor ing to t e direction of rotation of the support. v

The operation of the 'clutch is as follows: The shaft 2 maybe the shaft of an' electric -motor or other similar device to which the driving pulley 1v is secured. The rotating member of the motor is secured to thel sleeve or quill 4 and, consequently, when the motor is started, the shaft and the pulley to which the load may be assumed to be connected, is at rest. When the motor armature attains a predetermined speed of rotation, the centrifugal forces acting on the spring 6 will expand it, in opposition to the tension spring 7, forcibly into engagement with the inner cylindrical surface of the liange. 3. Frictional engagement between these parts will cause the pulley 1 and the load to revolve with the motor armature in a well known manner. The stops 14 and 15 prevent any material relative rotation between the support 5 and the spring ByI utilizing the spring 6 instead of s divided ring or some other member-,.1 find that the action of the .clutch is very positive and the outer surface of the spring continues to Patent-essen. 1, :1914;

9 and/10 are riveted, or otherwise l grip the inner surface of the flange very firmly as long as the speed is maintained.`

The clutch illustrated may, of course, be utilized for any suitable purpose and I intend that Vmy invention shall be limited only as specified in the appended claims.

lclaim as my invention:

1. The combination with two independently rotatable members having concentric annular surfaces, of' a helical spring held upon the inner annular surface against relative rotative movement and expansiblel by centrifugal force to engage the outer annular surface.

2. rlhe combination with -a driven shaft having an annular clutch member and a driving member havins an annular surface located within said c utch member, of a .helical spring mounted upon said annular surface and held thereon against relative rotative movement, and a tension spring for normally clamping the helical spring to said annular surface and the pull of which` is overcome by centrifugal force when the driving member.- attains a predetermined speed of rotation.

- l3'. 'A clutch comprising concentric driving and driven rotatable members and an interposed. circumferentially disposed helical spring that is constrained to turn with the driving member and is expansible by ntrifugal force to e'ect a frictional locking engagement between said members.

4. YA4 friction clutch comprising a hollow cylindrical member, an independently rotatable driving member, a circumferentially'int'erposed helical springthat is expansible-by centrifugal force to engage the hollow cylindrical member and is constrained to turn with the driving member,

and means acting upon said spring in op-` position to centrifugal force.

5. A friction clutch comprising a pair of concentric independently rotatable members, an inter osed hellcal spring having i in engagement with the peripheral groove of the inner member, and means for preventing rotative movement of said spring in said groove.

In testimony whereof, I havehereunto i subscribed my name this 31st day of-July,

f ALBERT KIN GSBURY. Witnesses:v

BERTRAND P. Rowe, B. B. Hines. 

